Chemical heater



June 17, 1924.

P. L. BERKEY CHEMIFJAL HEATER Filed May 9, 1921 FIG. 1.

FiE. 2'.

INVENTOR BY W ATTORNEYS Patented June 17, 1924.

\ UNITED STATES PATENT OFFICE.

flammable, of the person breathing them. In other of.

PAUL L. BERKEY, O-F ZELIENOPLE. PENNSYLVANIA, ASSIGNOR OF ONE-HALF TO 4ROBERT C. ROY, OF PITTSBURGH, PENNSYLVANIA.

CHEMICAL HEATER.

Application filed May 9,

p be heated by reaction thereof.

The objects of the invention are to provide a container, and associatedparts, adapted to carry a charge of chemicals and to receive anadditional chemical designed to produce a reaction in the containerwhereby'to generate heat. A further object is to provide such .a devicein a form that will quickly generate the heat and which will distributechemicals so that a reaction of the desired intensity may be produced. Afurther object is to provide means for neutralizing or absorbing anynoxious gases that may be generated by the reaction of chemicals withinthe container. A further object is to provide a suitable mixture of drychemicals, and in a special form for devices of the class described.Other uses and advantages will appear from the following specification.

Referring to the drawings Fig. 1 is a plan of this invention embodied inthe form of a container adapted for uses to which the ordinary hot waterbottle is applied; Fig. 2 is a central section through the container;Fig. 3 is a plan view on the line III III of Fig. 2; and Fig. 4 is apartial section on the line IVIV of Fig. 2.

I am aware that it has been proposed to utilize the heat generated bythe reaction of certain chemicals for the purpose of heating. Therefore,I do not claim the broad idea of heating utensils by means of chemicalreaction, nor do I claim' the specific chemicals referred to herein forthat purose.

p The chief difliculty with devices of this class which have heretoforebeen made is that they have generated gases, which were disagreeable, oreven dangerous, being in or irritating to the nose and throat suchdevices where a crystallization of 1921. Serial no. 468,156.

'tain in operation and tend to deteriorate rapidly. This renders devicesbased on the crystallization principle expensive and comparativelyineflicient.

I have overcome these difficulties by the invention now to be described.

Referring to the drawings, which illustrate a container in the form ofan ordinary metal hot water bottle, I employ a container composed of twopan shaped metal plates united at their edges to form a unitary casingor bottle 1. This has two openings, into one of whieh is fastened by anysuitable means an interiorly threaded member 2, having an in-turnedflange 3 upon which a ring 4 is adapted to seat. To this ring isattached a conical shaped wire screen member 5. adapted to screw intothe member 2,: and to clamp the ring 4 which carries the screen, betweenthe lower end of the sleeve 6 and flange 3, as clearly illustrated inFig. 2.

If desired the ring 4 may be soldered either to the flange 3 or to thebottom of the shell 6, in order to make the screen unitary with one orthe other of these members. A metal cap having a cylindrical portion 7and an enlarged head 8 is provided, and this is adapted to slip over theshell 6, to form a fluid-tight joint therewith. This fit is made looseenough so that the cap may be readily removed, and also that it willblow off if any large amount of pressure is generated within the bottle.The wire screen member 5 tapers to a point, which extends past thecenter of the bottle but terminates some distance from the oppositewall.

A short piece of tubing 6, is

The other opening in the bottle has fas-' V ring 12 to which is attacheda cup shaped screen member 13. Theclosure member has a threaded bodyportion 14 and an external knurled head 15, and carries a screen 16, andis adapted to screw into the member 10 and to clamp the ring 12 betweenitself and the flange 11, ,as shown clearly at the right of Fig.2. Itwill be understood that the wire screen forming the members 5, 13 and 16may be made of any suitable perforated material, such as wire mesh, andwith any de sired size of openings, according to the size of theparticles that are to be retained thereby. However the screen 5 hasopenings sufliciently large to permit the escape of water therethroughand screen 13 and screen 16 are sufficiently open to permit free escapeof gas.

Thiscontainer or bottle is preferably filled with small tablets, of anydesired size and shape. The individual pellets are made up of certainchemicals below described, and are mixed ina finely powdered state, andthen dry pressed, while hot, into the form of pellets under greathydraulic pressure. The result is that these pellets are very hard,

out great expense, and in order to prevent.

disintegration and coalescing of the pellets, to open the grainsallowing ready absorption of water, and to render the mass formed by thepellets in case they do run together more easily broken up. i

I have found that a good mixture for the purpose referred to consists ofpowdered aluminum about 35%, sodium hydroxide about 35%, and sand orother inert material about 30%. These proportions however are notcritical, and may be considerably varied,

' with satisfactory, although somewhat different results. The amounts ofaluminum and of caustic alkali should be substantially equal.

I prefer to mix these ingredients hot, so as to avoid any hygroscopicmoisture that may otherwise be present. After the chemicals have beenformed into the hydraulically pressed pellets, I prefer to seal them ina water-tight container, such as tin cans, until they are to be used. Anadditional advantage of the use of the chemicals in this bydraulicallypressed pellet form' is that they have greater specific gravity, ordensity, and therefore hold the heat longer than a mere loose mixture ofpowdered chemicals. In addition to that it is possible to pack morechemicals in a given space when they are used in the pellet form.Furthermore the pellets are easier to handle than powder, easier to putinto the container, easier to take out, and easier to shake up while init. I

have found that if pressed under suflicient pressure and with theproperproportions that these pellets will not break up even when thecomplete reaction below described has taken place.

I fill the container as shown in Fig. 2 about four-fifths full of thepellets above described. The screen 13' I fill with some medium whichwill absorb, neutralize or otherwise render harmless and unobjectionablethe gases generated by the reaction of .the chemicals. Charcoal is agood material for this purpose, and is the one I prefer to employ, as itis very cheap. It is used in granular form, of a size that will notescape through the screens 16 and 13, and it may be readily removed andrenewed, by

unscrewing the cap member 14. Instead of charcoal'I may use some of theso-called activated carbons which has been developed in connection withgas masks during the war. In addition to the charcoal,

I may place inside the screen 16 some additional element such as asponge with a perfumed chemical, or with some neutralizing chemical.

The container having been filled with the.

above described chemicals, preferably in the form of pellets, and thescreen 13 having been filled with charcoal or other absorbing andneutralizing medium, the device is ready for'use. The cap 7 is of such asize as to contain the proper amount of water for adding to the bottleto produce the desired partial reaction. The cap is filled with water,which is poured into the opening formed by sleeve 6. It is distributedby the screen 5 through a large area and comes in contact with thepellets of mixed caustic alkali and aluminum. Immediately a reactionsets in, which liberates hydrogen gas, and which generates intense heat.Ihave found that the small amount of water contained in the cap 7 willproduce enough heat to spread throu the entire massof chemicals, andthrougIi the wall of the container and heat the whole structure to atemperature above the boiling point of Water. The density of thechemicals is such that when so heated and the exterior of the containeris properly insulated such as by a woolen' cover it will retain forseveral hours a suflicient amount of heat for all uses for which theordinary hot water bottle is adapted. I have further discovered that ina container of the size of the standard hot water bottle, with thechemicals pre-,

ing a reaction suflicient to heat the structure up'as above described.

It will be understood that between heats it is desirable to shake thebottle up in order to cause the pellets of chemicals to be shiftedaround so that fresh ones may be exposed to the additional charges ofwater.

The reaction generates a considerable amount of gas but practically allof this is absorbed by the charcoal in the screen 13. Consequently evenwhen the reaction is at its most intense stage, practically no gasescapes, and therefore the bottle is entirely unobjectionable in thisrespect. Should too much water be added, so that a large volume of gaswould be suddenly generated, there is no danger of explosion since theonly effect would be to blow the cap 8 ofi, which would permit theimmediate escape of gas.

Furthermore, to prevent the sudden addition of too much water at any onetime, I may provide a disk 20, between the ring 4 and the end of sleeve6, this disk having a small perforation 21 in its center. This willprevent water from being added too fast, and eliminate the danger ofproducing a dangerous reaction.

The water that is added to cause the reaction is all consumed. The heatgenerated drives off all the moisture inside the container. Nomoisturecan be absorbed from the atmosphere when the device is cold,because the cap 8 covers the inlet and the charcoalabout the outletabsorbs moisture that might otherwise get into and be absorbed by thechemicals.

Although I have illustrated and described this invention as applied to asubstitute for the ordinary hot water bottle, it will be obvious thatthe invention may be utilized for other devices, such as firelesscookers, carbureter heaters, shaving mugs, smoothing irons, and thelike, where it is desired vto heat a receptacle or object quickly,without smoke, gas, or inflammable materials of any kind, and Where noextraneous source of heat is available.

I claim:

1. The combination of a casing, adapted to retain a charge of drychemicals therein adapted to generate heat in the'presence of water, agas outlet from the container, and a body of gas-absorbiug materialpositioned in the outlet. 2. The combination of a container adapted toreceive and hold heat generating chemicals and having an escape port forgases generated by the chemicals, and a medium adapted to absorb suchgases as they pass through the escape port. I

3. heat generating device comprising acontainer, an inlet, a screenedpassage leading from said inlet through the con tainer, an outlet, and ascreened chamber adjacent said outlet, the container being adapted tohold dry chemicals capable of generating heat in the presence of waterand the chamber adjacent the outlet being adapted to hold a medium forabsorbing gas generated by the said chemicals.

4. In a device of the class described a container adapted to hold dryheat generating chemicals, a screened passage leading through the bodyof the container, and a measuring cap, adapted to close the port leadinginto the said passage. such measuring-cap being adapted to holdsufiicient li uor to produce the desire reaction.

n testimony whereof, I sign In name. PAUL L. BE KEY. Witness:

EDWIN O. JoHNs.

